A Profile of Methylphenidate Exposures
Abstract
Introduction : Methylphenidate is prescribed commonly for children with attention deficit hyperactivity disorder. An estimated 2.8% of US youths aged 5 to 18 years use it for the management of this disorder. Despite the widespread use of methylphenidate, the demographics and outcome of intentional and unintentional exposures to methylphenidate have not been described. Methods : To profile human exposures to methylphenidate, a retrospective review of all reports to a certified regional poison information center during 1998 was conducted. Data analysis included patient demographics, reason for the exposure, dose ingested, clinical effects, and patient outcome. Results : There were 113 methylphenidate human exposures. The following table summarizes the values for selected parameters that were investigated: Age Group (Years) <6 6–12 13–19 >19 Mean Age ± SD 2.9 ± 1.4 8.5 ± 2.1 15.0 ± 1.6 33.0 ± 10.1 Mean Dose ± SD 13.6 ± 8.2 mg 26.8 ± 18.7 mg 106.8 ± 177 mg 70.0 ± 73.9 mg Unintentional 100% 80.8% 26.7% 44.5% Intentional 0% 19.2% 73.3% 54.5% Symptomatic 16.0% 30.8% 50.0% 54.5% Number of Patients 35 26 30 22 Conclusions : The majority of exposures in children ≤12 years of age involved unintentional ingestion of a sibling's medication, self-administration of an excessive therapeutic dose, or the administration of an inadvertent dose given by a caregiver. Methylphenidate abuse was common among adolescents and adults. Regardless of the reason for the exposure, the amount ingested, or treatment, all exposures had a favorable outcome. Pediatric doses of less than 1 mg/kg were not associated with adverse events.